package 齐祥进;

public class data2 {
    public static void main(String[] args) {
        Demo4Person d4 =new Demo4Person();
        d4.show(12,3);
    }

}
class Demo4Person{
    public void show( int a ,int b){
        System.out.println("矩形面积："+a*b);
        System.out.println("三角形面积："+a*b/2);
    }
}

